Windows 2k8 perormance in proxmox/kvm

[piotr.pawlowski]

Dear all,

I've been digging into this topic for several days but unfortunately I am still in same point.

Small background:
I have two Proxmox severs, first one, where current Windows 2k8 (VirtualMachine based on KVM) production server is running without any problems and second one, where we would like to migrate Windows VM.
First server has two SATA disks (7200rpm) in hardware RAID1 with core Proxmox installation (1.5)
Second server has two SAS disks (15k rpm) also in hardware RAID1 with Debian Squeeze and Proxmox (1.9) installed manually.

First server:

proxmox:~# pveversion -v
pve-manager: 1.5-10 (pve-manager/1.5/4822)
running kernel: 2.6.32-2-pve
proxmox-ve-2.6.32: 1.5-7
pve-kernel-2.6.32-1-pve: 2.6.32-4
pve-kernel-2.6.32-2-pve: 2.6.32-7
qemu-server: 1.1-16
pve-firmware: 1.0-5
libpve-storage-perl: 1.0-13
vncterm: 0.9-2
vzctl: 3.0.23-1pve11
vzdump: 1.2-5
vzprocps: 2.0.11-1dso2
vzquota: 3.0.11-1
pve-qemu-kvm: 0.12.4-1
ksm-control-daemon: 1.0-3

proxmox:~# kvm --version
QEMU PC emulator version 0.12.4 (qemu-kvm-devel), Copyright (c) 2003-2008 Fabrice Bellard

proxmox:~# pveperf /var/lib/vz/
CPU BOGOMIPS:      21334.11
REGEX/SECOND:      817464
HD SIZE:           876.38 GB (/dev/sda4)
BUFFERED READS:    58.34 MB/sec
AVERAGE SEEK TIME: 14.67 ms
FSYNCS/SECOND:     782.12
DNS EXT:           188.33 ms
DNS INT:           2.87 ms

Second server:

root@proxmox2:~# pveversion -v
pve-manager: 1.9-26 (pve-manager/1.9/6567)
running kernel: 2.6.32-6-pve
pve-kernel-2.6.32-6-pve: 2.6.32-55+ovzfix-1
qemu-server: 1.1-32
pve-firmware: not correctly installed
libpve-storage-perl: 1.0-19
vncterm: 0.9-2
vzctl: 3.0.29-3pve1
vzdump: 1.2.6-1
vzprocps: 2.0.11-2
vzquota: 3.0.12-3

root@proxmox2:~# kvm --version
QEMU emulator version 0.15.0 (qemu-kvm-devel), Copyright (c) 2003-2008 Fabrice Bellard

root@proxmox2:~# pveperf /var/lib/vz/
CPU BOGOMIPS:      18619.71
REGEX/SECOND:      813523
HD SIZE:           268.49 GB (/dev/sda7)
BUFFERED READS:    159.58 MB/sec
AVERAGE SEEK TIME: 4.86 ms
FSYNCS/SECOND:     10129.81
DNS EXT:           70.39 ms
DNS INT:           61.44 ms

Problem:

After installation, Windows VM on second server is running slower than on first one. What is more, I've noticed, that on second server, just after reboot, when Windows VM is not running, disk performance is normal but it drops when I start VM (I am checking it by dd if=ddfile of=/dev/null bs=8k command , where ddfile has 5.2Mb)

Things, which I already performed:

• tunning RAID controller (enabling better caching)
• changing Windows disk drivers from IDE to VirtIO
• disabling cache on VM level by adding cache=none to VMID.conf file

All above without any improvement.

The funniest thing is, that on first server, this one with slower SATA drives, everything is running fine

Does anybody have any idea what else can be done to improve disk performance on Windows VM?

To be honest currently I am thinking about downgrading KVM from 0.15 to 0.12.5 , but I have no idea if the problem is directly in KVM.

I appreciate any kind of help and support in this topic.

Regards
Piotr

 

[tom]

Dear all,

I've been digging into this topic for several days but unfortunately I am still in same point.

Small background:
I have two Proxmox severs, first one, where current Windows 2k8 (VirtualMachine based on KVM) production server is running without any problems and second one, where we would like to migrate Windows VM.
First server has two SATA disks (7200rpm) in hardware RAID1 with core Proxmox installation (1.5)
Second server has two SAS disks (15k rpm) also in hardware RAID1 with Debian Squeeze and Proxmox (1.9) installed manually.

1.9 on Squeeze is not supported. use 2.0 on squeeze.

 

[piotr.pawlowski]

Hi Tom,

Thank you for feedback.
If I run apt-get update && apt-get upgrade does it upgrade also Proxmox environment?

Regards
Piotr

 

[tom]

as you are on a unsupported mix of packages I assume you will run into further issues. I suggest you do a clean installation as no-one here tried what you do here.

upgrading 1.9 or 2.0 is always:

> aptitude update && aptitude full-upgrade (or apt-get update && apt-get dist-upgrade)

but 1.9 TO 2.0 is different - we provide an update script for this task soon.

 

[piotr.pawlowski]

Sounds reasonably.
However, Tom, are you sure, that such performance issues, which I am currently facing, will gone after upgrade to Proxmox 2.0 ?

Regards
Piotr

 

[hotwired007]

Sounds reasonably.
However, Tom, are you sure, that such performance issues, which I am currently facing, will gone after upgrade to Proxmox 2.0 ?

Regards
Piotr

i think what Tom is trying to say is that Debian Squeeze and Proxmox 1.9 are not compatible or not stable so dont use it.

Proxmox 2 is still in RC so when it is realeased all the iussues will be fixed - but not before.

Use 1.9 and then compare the issues.

 

[piotr.pawlowski]

So the best will be to install Proxmox 1.9 directly from ISO available on pve.proxmox.com , am I correct?
Debian 5 is not supported any more by contributors, while Debian 6 is not supported by Proxmox yet.

 

[tom]

2.0 (Squeeze based) will be release soon, so probably you just wait for that or you go with the RC1 and live with some bugs but you do not have to do the upgrade from 1.9 to 2.0 (which is a major upgrade).